21104340137 has 2 divisors, whose sum is σ = 21104340138. Its totient is φ = 21104340136.

The previous prime is 21104340119. The next prime is 21104340139. The reversal of 21104340137 is 73104340112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15950679616 + 5153660521 = 126296^2 + 71789^2 .

It is a cyclic number.

It is not a de Polignac number, because 21104340137 - 2⁸ = 21104339881 is a prime.

Together with 21104340139, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21104340139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10552170068 + 10552170069.

It is an arithmetic number, because the mean of its divisors is an integer number (10552170069).

Almost surely, 2^21104340137 is an apocalyptic number.

It is an amenable number.

21104340137 is a deficient number, since it is larger than the sum of its proper divisors (1).

21104340137 is an equidigital number, since it uses as much as digits as its factorization.

21104340137 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 26.

Adding to 21104340137 its reverse (73104340112), we get a palindrome (94208680249).

The spelling of 21104340137 in words is "twenty-one billion, one hundred four million, three hundred forty thousand, one hundred thirty-seven".